function isCheckCreateAdmin(){
        var question_title = $('#question_title').val();
        var username = $('#username').val();
        var email = $('#email').val();
        var phone = $('#phone').val();
        var description = $('#description').val();
        var emailReg = /^([\w-\.]+@([\w-]+\.)+[\w-]{2,4})?$/;
        if(question_title == '' || question_title == 'Câu hỏi của bạn...'){
            $('#errorTitle').show();
            $('#errorUserName').hide();
            $('#errorPhone').hide();
            $('#errorEmail').hide();
            $('#errorDescription').hide();
            return false;
        }
        if(username == '' || username=='Tên gọi của bạn...'){
            $('#errorUserName').show();
            $('#errorTitle').hide();
            $('#errorPhone').hide();
            $('#errorEmail').hide();
            $('#errorDescription').hide();
            return false;
        }
        if(phone == '' || phone == 'Số điện thoại của bạn...'){
            $('#errorPhone').show();
            $('#errorUserName').hide();
            $('#errorEmail').hide();
            $('#errorDescription').hide();
            $('#errorTitle').hide();
            return false;
        }
        if(email == '' || email == 'yourname@...'){
            $('#errorEmail').show();
            $('#errorDescription').hide();
            $('#errorTitle').hide();
            $('#errorPhone').hide();
            $('#errorUserName').hide();
            return false;
        }
        if(!emailReg.test(email)){
            $('#errorEmail').show();
            $('#errorDescription').hide();
            $('#errorTitle').hide();
            $('#errorPhone').hide();
            $('#errorUserName').hide();
            return false;
        }
        if(description == ''){
            $('#errorDescription').show();
            $('#errorTitle').hide();
            $('#errorPhone').hide();
            $('#errorUserName').hide();
            $('#errorEmail').hide();
            return false;
        }
}

function isCheckComment(){
    var comment_name = $('#comment_name').val();
    var comment_description = $('#comment_description').val();
    if(comment_name == '' || comment_name=='Nhập vào họ tên...'){
        $('#errUserName').show();
        $('#errDescription').hide();
        $('#errUserName').focus();
        return false;
    }
    if(comment_description == ''){
        $('#errDescription').show();
        $('#errUserName').hide();
        $('#errDescription').focus();
        return false;
    }
}

function isNumbericOnly(event){
    // Allow: backspace, delete, tab, escape, and enter
    if ( event.keyCode == 46 || event.keyCode == 8 || event.keyCode == 9 || event.keyCode == 27 || event.keyCode == 13 || 
        // Allow: Ctrl+A
        (event.keyCode == 65 && event.ctrlKey === true) || 
        // Allow: home, end, left, right
        (event.keyCode >= 35 && event.keyCode <= 39)) {
        // let it happen, don't do anything
        return;
    }
    else {
        // Ensure that it is a number and stop the keypress
        if (event.shiftKey || (event.keyCode < 48 || event.keyCode > 57) && (event.keyCode < 96 || event.keyCode > 105 )) {
            event.preventDefault(); 
        }   
    }
}